Cardiff Council's 'Usual Suspects' campaign carries the message: "There's no excuse for dropping litter."
The anti-grime crackdown will focus on three main points:
- Dog fouling
- Fly tipping
The council's waste team is also telling dog owners there is a fine of £75 if caught not cleaning up after their dogs.
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It will remain breezy with further blustery and at times thundery showers.
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Showers becoming increasingly wintry even to lower levels, bringing an ice risk.